Your car's alternator is a part of the engine, and its purpose is to continuously charge your car battery and its electrical components while the engine runs. Because of this, the alternator is considered a hard-working part and lasts between 40,000-100,000 miles depending on the number of electronics it charges, quality of the part and the driving conditions. This article discusses three essential aspects of alternator care.

1. Signs of imminent alternator failure

Because the alternator runs the car after the battery starts it, alternator failure will leave you stranded. Therefore, you should know possible signs of imminent failure so that car repair can be done promptly. They include:

• Pulsating headlights during night driving (dim to bright and back)
• Intermittent working of electrical components like the car radio, lights and power windows
• Car battery warning light coming on or running flat (not always) and other dashboard warning lights
• Squealing noises from your car engine (not always)
• A burning smell from the alternator or battery region on inspection
• Loose or snapped aux belt – this will often cause power steering failure, therefore, is easily diagnosable

Diagnosis and repair of alternators differ according to the car model; older models are easier and cheaper to diagnose, repair and/or replace.

2. Alternator maintenance tips

Proper maintenance can go a long way in extending your alternator's usable life. Besides, things, like installing power-heavy electronic accessories or jump-starting your car wrongly, can ruin your alternator before its time. These are some care tips to remember:

• Ensure the aux belt isn't overly tight as this can accelerate wear on alternator bearings. Fluid leaks within the alternator have a similar effect
• The first place to check if your battery light comes on is the alternator. In a properly-running system, your battery shouldn't run flat. During failure/malfunction, your electronic components will scramble for stored power in the battery, causing it to go flat.
• When replacement is needed, invest in high-quality branded parts with good warranty. Your mechanic can help you to check for this
• Ensure your engine parts are free of accumulated dirt/debris and replace the aux belt according to your service schedule

3. Tips for replacing your alternator

It's easy to get confused when you need to replace your alternator, as there are usually repaired, rebuilt and remanufactured alternators in the spare part market. Depending on your budget, the following are some things to expect when you buy any of the above options:

• Repaired – the least expensive option; involves replacement of a malfunctioning part in the alternator
• Rebuilt – alternator components are dismantled, tested and inspected. Malfunctioning or old parts are replaced, and the alternator is reassembled. The quality of the finished product heavily depends on the skill of its technician, however. This is moderately expensive, but it comes with a short warranty, commonly one year
• Re-manufactured – most expensive, but most reliable as it involves comprehensive inspection using strict guidelines and state-of-the-art equipment. It may even have alternator improvements. Should be done by a Factory Authorised Re-manufacturer and come with product warranty/quality guarantee.